[cogl/wip/cogl-1.14: 68/177] Fix flushing the stencil viewport clipping workaround

[Robert Bragg <rbragg src gnome org>]

commit 4fd7980e6d13eeb6727e5a457852ac1644cd0f69
Author: Neil Roberts <neil linux intel com>
Date:   Tue Nov 20 18:33:33 2012 +0000

    Fix flushing the stencil viewport clipping workaround
    
    There were two problems with the stencil viewport clip workaround
    introduced in afc5daab8:
    
    â When the viewport is changed the current clip state is not marked as
      dirty. That means that when the framebuffer state is next flushed it
      would continue to use the stencil from the previous viewport.
    
    â When the viewport is automatically updated due to the window being
      resized the viewport age was not incremented so the clip state
      wouldn't be flushed.
    
    I noticed the bugs by running cogl-sdl2-hello.
    
    This patch makes it so that the clip state is dirtied in
    cogl_framebuffer_set_viewport if the workaround is enabled.
    
    The automatic viewport changing code now just calls
    cogl_framebuffer_set_viewport instead of directly prodding the
    viewport values. This has the side-effect that it will also cause the
    journal to be flushed. This seems like the right thing to do anyway
    and presumably there would have been a bug before where it wouldn't
    have flushed the journal, although presumably this is extremely
    unlikely because it would have to have done a resize in the middle of
    painting the scene.
    
    Reviewed-by: Robert Bragg <robert linux intel com>
    
    (cherry picked from commit 0dca99ddf728c8d4e3003861a03e8a2beccf282d)

 cogl/cogl-framebuffer.c |   12 +++++++++---
 cogl/cogl-onscreen.c    |   12 +-----------
 2 files changed, 10 insertions(+), 14 deletions(-)
---
diff --git a/cogl/cogl-framebuffer.c b/cogl/cogl-framebuffer.c
index f7f2983..19f9cd5 100644
--- a/cogl/cogl-framebuffer.c
+++ b/cogl/cogl-framebuffer.c
@@ -449,6 +449,8 @@ cogl_framebuffer_set_viewport (CoglFramebuffer *framebuffer,
                                float width,
                                float height)
 {
+  CoglContext *context = framebuffer->context;
+
   _COGL_RETURN_IF_FAIL (width > 0 && height > 0);
 
   if (framebuffer->viewport_x == x &&
@@ -465,9 +467,13 @@ cogl_framebuffer_set_viewport (CoglFramebuffer *framebuffer,
   framebuffer->viewport_height = height;
   framebuffer->viewport_age++;
 
-  if (framebuffer->context->current_draw_buffer == framebuffer)
-    framebuffer->context->current_draw_buffer_changes |=
-      COGL_FRAMEBUFFER_STATE_VIEWPORT;
+  if (context->current_draw_buffer == framebuffer)
+    {
+      context->current_draw_buffer_changes |= COGL_FRAMEBUFFER_STATE_VIEWPORT;
+
+      if (context->needs_viewport_scissor_workaround)
+        context->current_draw_buffer_changes |= COGL_FRAMEBUFFER_STATE_CLIP;
+    }
 }
 
 float
diff --git a/cogl/cogl-onscreen.c b/cogl/cogl-onscreen.c
index 4aaa5de..3c1e148 100644
--- a/cogl/cogl-onscreen.c
+++ b/cogl/cogl-onscreen.c
@@ -387,17 +387,7 @@ _cogl_framebuffer_winsys_update_size (CoglFramebuffer *framebuffer,
   framebuffer->width = width;
   framebuffer->height = height;
 
-  framebuffer->viewport_x = 0;
-  framebuffer->viewport_y = 0;
-  framebuffer->viewport_width = width;
-  framebuffer->viewport_height = height;
-
-  /* If the framebuffer being updated is the current framebuffer we
-   * mark the viewport state as changed so it will be updated the next
-   * time _cogl_framebuffer_flush_state() is called. */
-  if (framebuffer->context->current_draw_buffer == framebuffer)
-    framebuffer->context->current_draw_buffer_changes |=
-      COGL_FRAMEBUFFER_STATE_VIEWPORT;
+  cogl_framebuffer_set_viewport (framebuffer, 0, 0, width, height);
 }
 
 void